WO2012045764A1

WO2012045764A1 - Electromotively actuated valve

Info

Publication number: WO2012045764A1
Application number: PCT/EP2011/067364
Authority: WO
Inventors: Ewald Schneider; Friedrich Menz
Original assignee: Ewald Schneider; Friedrich Menz
Priority date: 2010-10-08
Filing date: 2011-10-05
Publication date: 2012-04-12
Also published as: DE102010048901A1; EP2625450B1; EP2625450A1; ES2526438T3

Abstract

An electromotively actuated valve (10) is provided with a valve housing (11) on which an inlet connection (12) and at least one outlet connection (14) are provided, between which a flow duct (53) for a medium to be conducted through the valve (10) extends, and with an actuating member (31) which is actuated via an electric motor (54) and interacts with a valve seat surface (48) in order to close the flow duct (53), wherein the actuating member (31) is arranged coaxially in the electric motor (54) and is connected to the rotor (55) thereof in such a manner that rotation of the rotor (55) leads to an axial adjustment of the actuating member (31, 62). An external thread (59) is provided on the actuating member (31) and an internal thread (58), which is in engagement with the external thread (59), is provided on the rotor (55), and therefore the actuating member (31, 62) and rotor (55) form a helical gearing.

Description

Electromotive actuated valve

The present invention relates to an electromotively actuated valve having a valve housing, on which an input port and at least one output port are provided, between which a flow channel for a medium to be conducted through the valve extends, and with an actuated by an electric motor actuator, which cooperates to close the flow channel with a valve seat surface, wherein the actuator coaxially disposed in the electric motor and in such a way with the rotor in connection, that a rotation of the rotor leads to an axial displacement of the actuator. Valves for regulating and shutting off liquid or gaseous media are widely known from the prior art. The valves may be formed as a coaxial valve with a displaceable in the flow direction of the medium control tube, a solenoid valve with aufzudrückenden on the valve seat membrane or valve with shut-off, which is inserted into the flow channel to close this.

The operation of the control tube, diaphragm or shut-off, which are referred to together as an actuator in the context of the present invention, takes place via magnets, hydraulic or pneumatic, as well as electric motors.

The present invention is concerned with the development of electric motor-operated valves, in particular with electromotive actuated coaxial valves.

Such, but not electric motor actuated coaxial valve is known for example from DE 101 08 492 AI.

The known coaxial valves are used for regulating and shutting off liquid or gaseous media, which media can be chemically aggressive and can be present at high or low temperatures and at high pressures. Against this background, high demands are to be made on such coaxial valves in terms of tightness, mechanical reliability and ease of servicing.

Coaxial valves are used for example for the supply of machine tools with cooling lubricants that are supplied under high pressures available. In these applications, coaxial valves are therefore used because they are completely relieved of pressure, the upcoming pressure of the medium to be transported thus has no effect on the switching behavior. Furthermore, the medium to be controlled flows through the coaxial valve without appreciable flow deflection in the axial direction, wherein the resistance of the coaxial valve opposite the flowing medium is very low.

Coaxial valves have an axially displaceable in a valve housing mounted control tube, which is flowed through by the medium to be transported. The control tube cooperates with a valve seat surface on which the control tube rests in one of its axial end positions such that the coaxial valve is closed.

In its opposite axial end position, the control tube is spaced from the valve seat surface, so that the medium can flow freely through the coaxial valve.

DE 199 60 330 AI describes a coaxial valve in which the control tube is adjusted by a lever mechanism which is actuated from outside the valve housing via an electric actuator. This coaxial valve is structurally complex and voluminous.

DE 10 2005 028 584 AI describes a coaxial valve, wherein externally on a portion of the control tube, an outer groove-shaped helical groove is arranged, which is in engagement with a groove-shaped inner helical groove, which is provided on the inside of a drive sleeve which the control tube Coaxially surrounds. In the helical grooves run balls, so that the control tube and drive sleeve form a kind of ball screw.

The rotatably but axially immovably mounted in the valve housing drive sleeve is rotatably connected to the rotor of an electric motor, the is arranged coaxially with the control tube in the valve housing. The stator surrounding the rotor is rotatably mounted in the valve housing. In this way, the known Koaxilaventil should have a compact design with low weight. Nevertheless, the overall structure is complex and not very easy to service.

A comparable construction has a coaxial valve from WO 2009/021492 AI. In this coaxial valve, a spring assembly is additionally arranged between the drive sleeve and the control tube, via which the control tube is biased in the closed position, so that the electric motor can be de-energized in the closed position and the coaxial valve still remains securely closed.

The known coaxial valve is infinitely adjustable between open position and closed position, wherein the actuating time between two predetermined positions of the control tube is arbitrary. However, the electric motor must actively work in each open position of the coaxial valve against the force of the spring assembly, which brings a correspondingly high power consumption with it.

Corresponding disadvantages arise in a proportional valve of classical design, in which an electromagnet is used, which operates against the force of a closing spring. This solenoid must be permanently energized to keep the valve open. For constant adjustment and maintaining a desired degree of opening, a complex control is also required.

EP 2 228 891 A2 generally mentions the use of an electric motor for actuating an actuator of a valve via a motor shaft, which can be adjusted axially by the rotor of the electric motor.

Due to the stressful conditions of use is observed again and again that accumulate on the valve seat contaminants, on the one hand prevent a safe closing of the valve, on the other hand also affect the free flow of the medium through the open valve. To For this purpose known Koaxialventile be dismantled to remove the valve seat and clean.

In the known coaxial valves can be for this purpose a part of the valve housing in the longitudinal direction of the control tube, ie in the direction of fluid flow, solve and remove, whereupon then cleaned the valve seat or the valve seat can be exchanged.

It has now been found that due to the geometric conditions of this axial removal of the valve seat is often problematic. Before disassembling the valve body, the valve body often has to be dismantled by the machine on which it is mounted.

However, the then possible cleaning of the valve seat surfaces sometimes does not lead to the desired success, so that the valve seat must be replaced as a whole. For this purpose, the valve seat must be unscrewed from the removed from the housing housing part and a new valve seat to be screwed, whereupon the housing part is screwed back to the valve body, which then has to be mounted again on the controlled via the coaxial valve engine.

These measures are generally time consuming, so that the consequent downtime of the controlled machines together with the cost of the replacement parts represent a significant cost burden.

To overcome these problems, proposes the applicant of the present invention, not pre-published DE 10 2009 060 785, to form the valve seat surface on a replaceable sealing element, which arranged in a substantially transverse to the longitudinal direction opening of the valve housing is. Thus, it is no longer necessary to remove the entire valve seat together with a part of the housing for the purpose of cleaning, but it is possible to design a sealing element so that it can be taken so to speak transversely to the flow direction of the transported medium from the valve housing and after cleaning so also can be used again. For this purpose, the replaceable sealing element is arranged in an opening of the valve housing, which extends substantially transversely to the longitudinal direction of the control tube.

Because no longer the entire valve seat must be dismantled to clean the coaxial valve, the manipulations are much easier to perform, with the cleaning of a simple sealing element is much faster and more effective than with an entire valve seat.

In addition, after removing the sealing element and the flow path in the valve housing can be cleaned quickly and easily, because through the opening a lateral access to the region of the valve seat was created. Through this opening and the end face of the control tube can be agreed, which cooperates with the valve seat surface.

The coaxial valve described in the unpublished DE 10 2009 060 785, which is actuated by a control medium or an electromagnet, is thus much easier to service than the known coaxial valves.

Against this background, the present invention has the object, a valve of the type mentioned in such a way that it works energy-saving in a compact and structurally simple design and is easy to service.

In the valve mentioned above, this object is achieved in that on the actuator, an external thread and on the rotor befindlichem in engagement with the external thread internal thread is provided so that the actuator and the rotor form a helical gear, wherein external thread and Internal thread preferably form a self-locking helical gear. The object underlying the invention is completely solved in this way.

The inventor of the present application has in fact recognized that these disadvantages can be avoided in known valves by the use of an electric motor according to the invention, which moves the control tube or the plunger via a preferably self-locking helical gear in the desired position. The helical gear namely allows a structurally simpler and more space-saving design than in the known from DE 10 2005 028 584 AI and WO 2009/021492 AI coaxial valves.

If the helical gear self-locking, so the electric motor can be switched off after opening or closing the valve, because the control member can not be moved by axially acting on the control member forces.

The invention can thus be realized on the one hand in a coaxial valve with an axially arranged electric motor in which the medium flows axially through the electric motor, which receives a control tube for this purpose, which he can arbitrarily position about rotation of the rotor.

On the other hand, the electric motor can also be arranged off-axis, for example transversely to the flow direction, and thereby actuate a blocking element which cooperates with a sealing surface. Since the electric motor does not have to be flowed through by the medium here, it can possibly be constructed even smaller than with an axially arranged electric motor.

By choosing the pitch of the thread between the driven by the motor rotor and the externally threaded control and electric motors with low torque can spend high forces, so that the new valves not only proportional valves but also Replace pilot valves in which a small valve, the medium is controlled, then the large closing or opening pressure is applied.

In one exemplary embodiment, it is preferred if the valve is designed as a coaxial valve and the actuator is mounted as a control tube mounted displaceably in its longitudinal direction in the valve housing, which cooperates with the input port and the outlet port in such a way that when the coaxial valve is open the medium flows through, and which cooperates in one of its axial end positions with the valve seat surface for closing the coaxial valve, wherein the valve seat surface is preferably formed on an exchangeable sealing element which is arranged in a substantially transverse to the longitudinal direction opening of the valve housing.

In the context of the present application, "essentially transversely" is understood to mean an orientation which, although preferably perpendicular, ie perpendicular to the longitudinal direction, but also obliquely, that is to say at an angle to the longitudinal axis which is less than 90 °, but above 45 °.

The advantage here is that the valve seat surface is provided on a laterally removable from the valve seat sealing element, which is not only easy to remove and clean, but can also be produced as a cheap mass part that can be replaced without high costs. On the other hand, the sealing element can be manufactured with great accuracy and dimensional accuracy, since it has a simple geometric shape. This increases u.a. the service-friendliness of the new valve.

In a further exemplary embodiment, it is preferred if the valve is designed as a coaxial valve and the actuator as a control tube mounted displaceably in its longitudinal direction in the valve housing, which cooperates with the input port and the outlet port in such a way that it is open when the coaxial valve is open is flowed through by the medium, and in one its axial end positions with the valve seat surface for closing the coaxial valve cooperates, wherein the valve seat surface is formed on a preferably replaceable sealing element on which circumferentially distributed around a sealing element axis at least two valve seat surfaces are provided.

The new coaxial valve is not only very fast and easy to maintain in this way, it is also structurally very simple and allows, so to speak, the multiple reuse of the sealing element, so that not only the maintenance costs but also the replacement parts costs compared to the known coaxial valves clearly are reduced.

Depending on the diameter of the sealing element and the diameter of the control tube can thus be provided circumferentially distributed around a sealing element and three, four, five or even six valve seat surfaces, which makes a correspondingly frequent reuse of the sealing element possible.

The replaceable sealing element with the possibly more valve seat surfaces has particular advantages in cooperation with the actuated via the electric motor helical gear. Because of the quick exchange or cleaning ability of the valve seat surfaces can be ensured in a cost effective and service-friendly way that clean valve seat surfaces are available that allow a safe closing of the coaxial valve with a helical gear without spring preload. In a self-locking helical gear can then be switched off in the closed position, the electric motor, which could lead to problems with dirty or worn valve seat surfaces.

Of course, in the new valve, a safety spring may be provided, which ensures in case of power failure, that the valve is moved to its closed or open position. Generally, it is preferred if at least part of the valve housing forms a stator of the electric motor and this part of the valve housing is arranged coaxially with the rotor.

Here it is advantageous that the new valve is extremely small, because the stator forms at least a part of the valve housing, wherein the motor windings are arranged in this part of the valve housing.

In a further development, it is preferred if the sealing element is fixed to a sealing element holder which is releasably secured to the valve housing, wherein the sealing element is preferably seated on a support pin, which is arranged in the opening and at one end to releasably fixed to the valve housing and secured at its other end to the sealing element holder.

These measures are structurally advantageous, the sealing element holder carries on the one hand, the sealing element itself, but on the other hand also ensures at the same time for the completion of the opening provided in the valve housing to the outside, so that when the valve is open no medium can escape from the valve housing.

If the sealing element is arranged on a support bolt, it is also advantageous that the sealing element is statically supported in the opening in a simple manner and protected against bending. In this way it is ensured that in the closed state of the coaxial valve, in which the control tube rests with its end face against the valve seat surface on the sealing element, the sealing element is not displaced or bent. In other words, the support bolt, which is supported at its free end, for example, at the bottom of the opening in the valve housing and is firmly connected at its other end to the sealing element holder, ensures an accurate and permanently fixed positioning of the sealing element in front of the head tube. Particular advantages arise again with the possibly self-locking helical gear, because a permanently fixed positioning of the sealing element allows to dispense with closing springs and the electric motor, if necessary, in the closed position without power or switch to a lower holding current, which energetically Advantage is.

It is generally preferred if the sealing element is rotationally symmetrical to a sealing element axis, preferably distributed to the sealing element circumferentially about the sealing element axis at least two valve seat surfaces are provided.

In this measure, it is advantageous that a different area of the surface of the sealing element is provided as a valve seat surface by simply rotating the sealing element about the sealing element axis. In other words, if the valve seat surface used is so permanently polluted that it can not be cleaned, the sealing element does not need to be replaced, but it is so far rotated around the sealing element axis that a new surface area is available as a valve seat surface. The synergetic effects together with the helical gearbox have already been mentioned several times; they also result in a special way from this measure.

It is preferred if between the valve housing and sealing element at least one positioning arrangement is provided which defines at least two circumferential orientations of the sealing element in the valve housing.

In this measure, it is advantageous that the angular orientation of the sealing element is fixed in the valve housing from the outset, so that there is no risk that the sealing element has not been rotated far enough to the contaminated valve seat surface out of engagement with the head tube bring. Furthermore, the positioning arrangement ensures that the available surface of the sealing element is optimally utilized, ie the sealing element is not turned too far when a soiled valve seat surface is brought out by rotating the sealing element from the region of the seal.

This positioning arrangement can be arranged between the sealing element and the valve housing, the sealing element and the sealing element holder or the sealing element holder and the valve housing. It is important that after removing the sealing element holder of the valve housing, the still sitting on the sealing element holder sealing element is exactly as far rotated and then locked again that a new valve seat surface is provided for cooperation with the head tube.

It is preferred if the positioning arrangement comprises a dowel pin which sits firmly at one end in a first bore and at its other end with distributed around the sealing element axis arranged second bores cooperates.

The second holes are circumferentially spaced from each other so as effective valve seat surfaces are provided on the surface of the sealing element.

The second holes may be provided both on the sealing element and on the sealing element holder or the valve housing, wherein preferably the second holes are provided on the sealing element and the dowel pin is seated inside the sealing element holder.

When contamination of the coaxial valve according to the invention now only the sealing element holder has to be detached from the valve housing and pulled out together with the sealing element from the opening in the valve housing. Thereafter, the sealing element is cleaned and in the event that the previously used valve seat surface is no longer applicable, on the support pin so far away from the sealing element holder until the dowel pin out of engagement with the second drill hole. reached. Then, the sealing element is rotated until the next of the second holes facing the dowel pin, whereupon the sealing element is pushed back completely onto the support pin. Thereafter, the sealing element holder is placed with the sealing element vorderst again on the opening and then screwed to the valve housing.

By these simple measures is now a new valve seat surface for cooperation with the head tube available without the sealing element itself had to be replaced. Also by this measure, the already mentioned synergetic effects arise in a special way together with the helical gear.

It is still preferable if the or each valve seat surface is formed on a cylindrical surface, a spherical surface, a conical surface or a flat surface of the sealing element.

These various forms of valve seat have their particular advantages, but are known per se from the prior art.

Finally, for the sake of completeness, it should finally be mentioned that the new coaxial valves can also be interlocked to form multiple modules, wherein the input connections and / or output connections can be connected to common fluid distributors.

Especially with this block, the particular advantages of the new coaxial valve, because the respective sealing element can now be taken out laterally from the respective valve body, cleaned, possibly rotated or replaced and then used again without the complete valve body are dismantled got to. It is also not necessary to remove the valve housing from the block before the valve seat surfaces can be cleaned or replaced. In addition, the blocking is particularly space-saving possible with a coaxially arranged in the valve housing electric motor. Nevertheless, the sealing elements can be easily replaced or cleaned because of their arrangement according to the invention.

The electromotive drive with optionally self-locking helical gear can also be used for other valve designs in which either the actuator is designed as a plunger and the valve seat surface is associated with a membrane which is pressed to close the flow channel via the plunger on the valve seat , or the actuator is designed as a plunger and the valve seat surface is arranged at an inlet opening in the flow channel, wherein the plunger has on its end face a sealing surface which is pressed to close the flow channel on the valve seat surface.

Further advantages will become apparent from the description and the accompanying drawings.

It is understood that the features mentioned above and those yet to be explained not only in the particular combination given, but also in other combinations or alone, without departing from the scope of the present invention.

Embodiments of the invention are illustrated in the drawings and are explained in more detail in the following description. Show it:

Figure 1 is a perspective view of a coaxial valve with removed sealing element holder and removed sealing element.

Figure 2 is a highly schematic longitudinal section through the valve housing of Figure 1, viewed along the line II-II of Fig. 3. FIG. 3 shows a highly schematic longitudinal section through the valve housing of FIG. 1, seen along the line III - III from FIG. 2; FIG.

Fig. 4 is a view like Figure 3, but with the coaxial valve open.

Figure 5 is a perspective view of the sealing element holder, with four sealing elements shown in perspective, which can be selectively pushed onto the support pin of the sealing element holder.

Fig. 6 is a view as in Figure 2, but with an inventively provided electric motor for actuating the control tube, above in the closed and down in the closed state.

Fig. 7 is a view as in Figure 6, but with a moving over the electric motor ram for actuating a membrane. and

Fig. 8 is a view as in Fig. 7, but with a plunger, at the

End face a sealing surface for closing an inlet opening is arranged.

Fig. 1 shows a perspective view from above schematically and not to scale a coaxial valve 10 with a valve housing 11 to which an input port 12 and an output port 14 are provided for a to be guided through the coaxial valve 10 medium, symbolized by arrows 15 is.

Input terminal 12 and an output terminal 14 are formed as screw connections, via which the coaxial valve 10 can be connected to manifolds for the medium 15, wherein a plurality of coaxial valves 10 are arranged side by side and thus "blocked" can be, as in the prior art is well known. On the side of the valve housing 11, a first control port 16 and a second control port 17 are provided, through which in the manner to be described control medium into the interior of the valve housing 11 is passed to open the coaxial valve 10 or terminals, or connections be performed for an electric motor in the interior, as it can be used for the embodiment of FIG.

The valve housing 11 has on its upper side 18 an opening 19, which extends transversely to the flow direction of the medium 15 between the input terminal 12 and the output terminal 14.

Down in the opening 19, a front end 21 of a not shown in Fig. 1 control tube is shown, which comes in the closed state of the coaxial valve 10 with a sealing element 22 shown above the opening 19 into abutment.

Above the sealing element 22, a sealing element holder 23 is provided, from which a support pin 24 protrudes downwards, onto which the sealing element 22 with its passage opening 25 can be pushed.

When mounting the sealing element 22 and the sealing element holder 23 on the valve housing 11, the sealing element 22 is first pushed onto the support pin 24. Thereafter, the sealing element 22 is inserted into the opening 19, whereby the sealing element holder 23 comes to rest on the upper side 18 of the valve housing 11. Thereafter, the sealing element holder 23 is fastened with screws 26 to the valve housing 11, for which purpose in the top 18 threaded bores 27 are provided.

Even if the coaxial valve 10 is now blocked at its input port 12 and / or at its output port 14 with further coaxial valves 10 and connected to common media lines, but the Sealing element 22 removed at any time and cleaned and replaced if necessary. For this purpose, it is only necessary to loosen the screws 26 and deduct the sealing element holder 23 with the sealing element 22 carried by it from the valve housing 11.

Thereafter, the sealing member 22 can be removed and cleaned by the support pin 24. Likewise, it is possible to clean through the opening 19 through the interior of the valve housing 11, in particular the front end 21 of the control tube, not shown in Fig. 1. Likewise, the flow in the outlet port 14 can be easily cleaned without the outlet port 14 having to be dismantled further.

After the sealing element 22 has been cleaned and replaced if necessary, it is pushed back onto the support pin 24 and then mounted in the manner already described together with the sealing element holder 23 in or on the valve housing 11.

The sealing element 22 according to FIG. 1 can be plugged onto the supporting bolt 24 in different angular orientations, so that different regions of its lateral surface 28 are available as a valve seat surface for the front end 21.

In Fig. 1 is still denoted by 29 a sealing element axis, which represents the axis of symmetry of the rotationally symmetrical sealing element 22, which is cylindrical in the embodiment shown. In the direction of the sealing element axis 29, the sealing element 22 is pulled out of the valve housing 11 or inserted into this again.

Fig. 2 shows a highly schematic longitudinal section through the coaxial valve 10 of FIG. 1, viewed along the line II-II of Fig. 3, which in turn represents a schematic longitudinal section along the line III-III of Fig. 2. In other words, FIG. 3 shows a longitudinal section parallel to the upper side 18, while FIG. 2 shows a longitudinal section transversely to the upper side 18, ie parallel to one of the two side surfaces of the valve housing 11.

The sectional views of Figures 2 to 4 are very schematic, they show only the essential elements of the coaxial valve 10th

In Fig. 2 it can be seen first that in the valve housing 11 in the longitudinal direction 30 slidably already mentioned in connection with FIG. 1 control tube 31 is mounted. This control tube 31 extends from the inlet port 12 to the sealing element 22 and carries the medium 15. In the closed position of the coaxial valve 10 shown in Fig. 2, the control tube 31 is located with its front end 21 on the lateral surface 28 of the sealing element 22. At its other end 32, the control tube 31 is in communication with the input port 12.

On the control tube 31, which is designed as a sleeve, a piston 33 is provided, which serves as an anchor for an electromagnet 34 in the embodiment of FIG.

In the valve housing 11, a valve spring 35 is still arranged, which is supported at one end on an inner end face 36 of the valve housing 11 and the other end on a front side 37 in a blind bore 38 of the piston 33 is supported. In this way, the valve spring 35 pushes the piston 33 in Fig. 2 to the left, ie in the closed position of the coaxial valve 10th

In this position, the front end 21 of the control tube 31 is located on the lateral surface 28 of the sealing element 22 so that medium 15 can not escape from the control tube 31. Now, if the electromagnet 34 is energized, it pulls the acting as an anchor piston 33 in Fig. 2 for 3 to 5 mm against the force of the valve spring 35 in the longitudinal direction 30 to the right, so that the front end 21 of the head tube 31 lifts off from the lateral surface 28 of the sealing element 22. This stroke depends on the nominal size, with a stroke of 3 - 5 mm, for example, for a nominal diameter of the input and output connection of 10 mm.

Medium 15 can now flow into the opening 19 and from there to the outlet port 14.

In Fig. 2 can still be seen that the sealing element 22 carrying support pin 24 inserted with its free end 39 in a blind bore 41 of the valve housing 11. In this way, the support pin 24 is releasably secured to the valve housing 11. On the other hand, since the support bolt 24 is fixedly connected to the seal member holder 23, it supports the seal member 22 when the seal member 23 is screwed to the valve housing 11 so that it does not bend under strong pressure of the medium 15 but remains in its position in which it is safe cooperates with the front end 21 of the control tube 31.

As already mentioned, the cylindrical sealing element 22 is rotationally symmetrical to the sealing element axis 29, so that it can be plugged around the sealing element axis 29 on the support pin 24 in any desired angular position.

In this way it is possible, after disassembling the sealing element 22 to rotate it by a certain angle on the support pin 24, so that a new area of its surface 28 with the front end 21 of the control tube 31 cooperates when the sealing element 22nd was again mounted in the valve housing 11. In order to make optimal use of the surface 28 of the sealing element 22, a positioning arrangement is provided between the valve housing 11 and the sealing element 22, which is formed by a dowel pin 42 which sits firmly in a first bore in the sealing element holder 23 and optionally in second holes 43 of the sealing element 22 can engage. The distribution of the second bores 43 in the sealing element 22 about the sealing element axis 39 thus determines the various areas of the lateral surface 28, which can cooperate as a valve seat surface with the front end 21.

In Fig. 3, the coaxial valve 10 of FIG. 1 is shown in a section parallel to the top 18.

In the case of the coaxial valve 10 from FIG. 3, instead of the electromagnet 34, a control medium 44 is now provided as a control device for moving the piston 33, which can optionally be conducted into the valve housing 11 via the control connections 16 or 17.

If control medium 44 is directed into the first control port 16, this pushes the piston 33 to the left and closes, supported by the valve spring 35, the coaxial valve 10 by the control tube 31 with its front end

21 on the formed by the lateral surface 28 valve seat surface of the sealing element

22 is pressed.

If, however, control medium 44 is passed through the second control port 17 into the interior of the valve housing 11, the coaxial valve 10 is opened, the piston 33 thus moved in Fig. 3 against the force of the valve spring 35 to the right, so that the front end 21 out of engagement with the lateral surface 28 passes.

Medium 15 can now pass from the control tube 31 into the opening 19 and from there to the outlet port 14. This state is shown in FIG. 4.

Thus, Fig. 3 shows the control tube 31 in its one axial end position in which the coaxial valve 10 is closed, while Fig. 4 shows the control tube 31 in its other axial end position in which the coaxial valve 10 is opened.

In Fig. 5, the sealing element holder 23 is shown in perspective with support pin 24, wherein along the sealing element axis 29 four different sealing elements 22, 45, 46 and 47 are shown, which can be selectively slid onto the support pin 24.

Sealing element 22 is the already known cylindrical sealing element, the cylindrical surface 28 is used directly in different angular configurations as a valve seat surface and is provided for this purpose with 5 second holes 43.

Sealing element 45 has a ball surface as a valve seat surface 48, which in turn can interact directly in different angular configurations directly with a now circular-shaped end face end 21 of the control tube 31.

Sealing element 46 has five flat surfaces as a valve seat surface. Accordingly, a total of five second bores 43 are associated with the fitting pin 42 seated in the sealing element holder 23 and not visible in FIG. 5, so that the sealing element 46 can be attached to the support pin 24 in five different angular orientations around the sealing element axis 29.

Finally, sealing element 47 has, as a sealing element surface 51, four truncated cones, whose lateral surface 52 serves as a valve seat surface. Accordingly, four second holes 43 are provided on the sealing element 47. It should be noted that all sealing elements 22, 45, 46, 47 are arranged rotationally symmetrical to the sealing element axis 29.

Fig. 6 shows a coaxial valve 10 in a representation as in Fig. 2, in which case the actuation takes place via an electric motor 54, the control tube 31 between its closed position shown in Fig. 6 above and its in Fig. 6 below shown open position in the longitudinal direction 30, ie axially displaced and acts as part of a flow channel 53, the input terminal 12 and output terminal 14 connects to each other. The electric motor 54 has not shown motor windings, which are mounted in the circumferential direction and longitudinally fixed in the valve housing 11, which thus simultaneously forms the stator of the electric motor 54 ..

In other words, at least part of the valve housing 11 simultaneously serves as a stator 56 for the electric motor 54, wherein this part of the valve housing is arranged coaxially with the rotor 55.

In the thus formed stator 56 is rotatably seated a rotor 55, which is formed on its inner circumference 57 as a nut, so with internal thread 58. The rotor 55 is screwed with its internal thread 58 on an external thread 59, which is provided on the outside of the control tube 31. Rotor 55 and control tube 31 thus form a helical gear.

The electric motor 54 is thus arranged with its stator - ie the corresponding part of the valve housing 11 - coaxial with the rotor 55. The control tube 31 is arranged coaxially in the electric motor 54 and is connected via the helical gear in such a way with its rotor 55 in connection that a rotation of the rotor 55 leads to an axial displacement of the control tube 31.

6 to 8, the electric motor 54 is only indicated schematically, on the representation of seals, bearings, fasteners, electrical connections and other common components was for reasons of Clarity omitted. Although the electric motor 54 is shown as an internal rotor, that is, with a rotor 55 rotatably mounted inside the stator 56, it can also be designed as an external rotor.

The electric motor 54 is a servomotor of any type, which is designed in the manner of a torque motor as a gearless direct drive with a hollow shaft.

In other words, the rotor 55 of the electric motor 54 has a central bore and is formed as a nut. When rotating the rotor 55, the control tube 31 is moved in this manner in accordance with the pitch of the inner and outer threads 58, 59 in the manner of a threaded spindle. If the thread is self-locking, although the control tube 31 can be displaced by rotation of the rotor 55, the control tube 31 is unable to rotate the rotor 55, even if the motor windings of the stator are de-energized.

In Fig. 6 above, the coaxial valve 10 is shown in the closed state, the control tube 31 thus abuts against the sealing element 22, which in the embodiment of Fig. 6 has a spherical surface as a valve seat surface 48, so it corresponds to the sealing element 45 Fig. 5.

Otherwise, the illustration in FIG. 6 corresponds to the representation of FIG. 2, whereby identical reference symbols have also been used for identical features, so that reference may be made in this respect to the above description.

Due to the self-locking by a suitable choice of the thread pitch thread between the control tube 31 and the rotor 55, the coaxial valve 10 of FIG. 6 can be used as a proportional valve. Depending on the distance of the front end 21 of the control tube 31 to the sealing surface 48 can between the maximum flow - as in Fig. 6 below - and the Closed state - as in Fig. 6 above - any intermediate value are taken, so that variable flow rates are adjustable.

For the setting of such intermediate value, on the one hand, a flow meter can be provided, which together with an actuator ensures in a closed control loop that the control tube assumes the distance to the sealing surface, which ensures the corresponding flow. The electric motor 54 can then be de-energized, since the axial position of the control tube 31 is not changed because of the self-locking thread.

Alternatively or in addition to the flow meter, a position sensor for the control tube 31 may be provided, via which the distance between the front end 21 of the control tube 31 and the sealing surface 48 is measured. Also, this measured value can be used in a control loop to set a desired distance between the front end 21 of the control tube 31 and the sealing surface 48.

If the coaxial valve 10 is then used as a proportional valve, the dependence of the flow must be deposited by the said distance in the control. At a desired flow can then be determined from a table or a mathematical function of the distance to be set between the front end 21 of the control tube 31 and the sealing surface 48.

The electric motor 54 then forms together with a suitable servo controller a servo drive, which is position or flow controlled via the control loop.

If the valve is not to be used as a proportional valve, neither flow meter nor path measuring system are required, the control tube 31 is then only reciprocated between the two end positions, which in Fig. 6 are shown. To ensure that the end positions are reached, either the motor winding can be energized for a sufficient period of time, or the current flow through the motor winding is detected by measurement and detected by a change in the current flow that the control tube 31 has reached one of its end positions and does not move on ,

This electromotive drive of FIG. 6 can also be used for other valve designs, as shown in FIGS. 7 and 8.

In Fig. 7, a valve 60 is shown in the manner of a solenoid valve in which a membrane 61 is provided, which is pressed by a plunger 62 on a valve seat surface 63 which is mounted on a blocking element 64 in the flow channel 65 between the input terminal 12th and the output terminal 14 is arranged. Again, the stator 56 is formed by a part of the valve housing 11.

In FIG. 7 at the top, the membrane 61 is unactuated, so that free flow through the valve 60 is possible. In Fig. 7 below, the membrane 61 has been pressed by the plunger 62 so far down that the membrane 61 rests on the valve seat surface 63 and the flow is interrupted.

The actuation of the plunger 62 via the electric motor 54, which is constructed with stator 56 and rotor 55, as has already been described in connection with FIG. 6. However, the electric motor 54 is not arranged coaxially with the flow channel 65, but transversely thereto.

In contrast to FIG. 6, in the case of the valve 60 from FIG. 7, the medium also does not have to flow through the rotor 55, so that the electric motor 54 can be made smaller in construction since the rotor 55 is only coaxial with it extending ram 62 must receive on which the external thread 59 is provided, which is in engagement with the internal thread 58 of the rotor 55. Rotor 55 and plunger 62 thus also form a screw thread. Again, it is possible to provide a self-locking thread, so that the valve 60 of FIG. 7 in the above explained in connection with FIG. 6 sense can act as a proportional valve.

Another valve 70 is shown in Fig. 8, where an electric motor 54 is used with plunger 62 as shown in Fig. 7. In this embodiment, however, no diaphragm is moved, but the plunger 62 has at its free end face 71 a sealing surface 72 which comes to rest on an inlet port 73 which forms the valve seat surface and the input port 12 with a flow channel 65, from which the Medium then passes to the output terminal 14.

For the function and structure of the electric motor 54, the above mentioned in connection with Figs. 6 and 7 applies.

In all three embodiments of the valve 10, 60, 70 with electric motor 54 input port 12 and output port 14 may be provided with large diameters, since the applied for closing high forces on the basis of the pitch of the thread 58, 59 between the rotor 55 and control tube 31st or plunger 62 may be selected so that even with small motors very high forces can be transmitted.

Thus, the valves 10, 60, 70 according to the embodiments in FIGS. 6 to 8 replace pilot-operated valves in which by means of the media pressure, the required high forces are applied to control the large diameters can.

Claims

claims

An electromotively actuated valve (10, 60, 70) having a valve housing (11) on which an input port (12) and at least one output port (14) are provided, between which a flow channel (53, 65) for through the Valve (10, 60, 70) extending medium, and with an electric motor (54) actuated actuator (31, 62) for closing the flow channel (53, 65) with a valve seat surface (28, 48, 49, 52, 63, 73) cooperates, wherein the actuator (31, 62) arranged coaxially in the electric motor (54) and in such a way with its rotor (55) is in connection that a rotation of the rotor (55) to an axial displacement of the actuator (31, 62), characterized in that on the actuator (31, 62) has an external thread (59) and on the rotor (55) in engagement with the external thread (59) located internal thread (58) is provided, so that Actuator (31, 62) and rotor (55) form a helical gear.

2. Valve according to claim 1, characterized in that the external thread (59) and the internal thread (58) form a self-locking screw thread.

3. Valve according to claim 1 or 2, characterized in that the valve (10, 60, 70) as a coaxial valve (10) and the actuator (31, 62) as in its longitudinal direction (30) slidably mounted in the valve housing (11) Control tube (31) is formed, which cooperates with the input port (12) and the output port (14) such that it is flowed through with an open coaxial valve (10) from the medium, and in one of its axial end positions with the valve seat surface (28, 48, 49, 52) for closing the coaxial valve (10) cooperates, wherein preferably the valve seat surface (28, 48, 49, 52) on an exchangeable sealing element (22, 45, 46, 47) is formed, which in a substantially transverse to the longitudinal direction (30) extending opening (19) of the valve housing (11) is arranged.

4. Valve according to one of claims 1 to 3, characterized in that the valve (10, 60, 70) as a coaxial valve (10) and the actuator (31, 62) as in its longitudinal direction (30) displaceable in the valve housing (11 ) is formed, which cooperates with the input port (12) and the output port (14) such that it flows through the medium when the coaxial valve (10) is open, and in one of its axial end positions with the Valve seat surface (28, 48, 49, 52) for closing the coaxial valve (10) cooperates, wherein the valve seat surface (28, 48, 49, 52) on a preferably replaceable sealing element (22, 45, 46, 47) is formed on the circumferentially about a sealing element axis (29) distributed at least two valve seat surfaces (28, 48, 49, 52) are provided.

5. Valve according to one of claims 1 to 4, characterized in that at least part of the valve housing 11 forms a stator of the electric motor (54) and this part of the valve housing (11) is arranged coaxially with the rotor (55).

6. Valve according to claim 3 or 4, characterized in that the sealing element (22, 45, 46, 47) on a sealing element holder (23) is fixed, which is releasably attached to the valve housing (11).

7. Valve according to claim 6, characterized in that the sealing element (22, 45, 46, 47) on a support pin (24) sits, which is arranged in the opening (19) and at one end (39) releasably attached to the Valve housing (11) fixed and fixed at its other end to the sealing element holder (23).

8. Valve according to one of claims 3 to 7, characterized in that the sealing element (22, 45, 46, 47) is rotationally symmetrical to a sealing element axis (29).

9. Valve according to one of claims 3 to 8, characterized in that on the sealing element (22, 45, 46, 47) circumferentially around a sealing element axis (29) distributed at least two valve seat surfaces (28, 48, 49, 52) are provided.

10. Valve according to one of claims 3 to 9, characterized in that between the valve housing (11) and sealing element (22, 45, 46, 47) at least one positioning arrangement (42, 43) is provided, the at least two circumferential orientations of the sealing element ( 22, 45, 46, 47) in the valve housing (11) determines.

11. Valve according to claim 10, characterized in that the positioning arrangement (42, 43) comprises a dowel pin (42) which is seated at its one end fixed in a first bore and distributed at its other end to the sealing element axis (29) second bores 43 cooperates.

12. Valve according to one of claims 3 to 11, characterized in that the or each valve seat surface (28, 48, 49, 52) on a cylindrical surface (28), spherical surface (48), conical surface (52) or flat surface (49) of the Sealing element (22, 45, 46, 47) is formed.

13. Valve according to claim 1 or 2, characterized in that the actuator (31, 62) as a plunger (62) and the valve seat surface (63) is associated with a membrane (61) for closing the flow channel (65) over the Push rod (62) on the valve seat surface (63) is pressed. Valve according to claim 1 or 2, characterized in that the actuator (31, 62) as a plunger (62) and the valve seat surface (73) at an inlet opening in the flow channel (65) is arranged, wherein the plunger (62) at its End face (71) has a sealing surface (72) which is pressed to close the flow channel (65) on the valve seat surface (73).